[Grand Tourer]

Looking for advice. I’m in the UK I have a 2004 W211 E320 petrol with 117,000 miles. I’ve owned it 3 years and it’s been generally reliable but in retrospect, I don’t think I bought a well looked after vehicle and it already has a faulty parking sensor which is not a cheap fix with the bumper off. Anyway, in December I spent £1500 on new discs and pads and Michelin tyres and a few other repairs. Then I started getting terrible mpg and error messages. The garage have just read the fault codes and I’ve got the beginnings of a failing ABS pump (causing grazing brake pads, hence poor mpg) and leakage in the suspension air compressor. Each of them expensive fixes more than the value of the car unless I use reconditioned parts. I had been considering changing it anyway for something cheaper to run and in better condition but it’s such a lovely car to drive. I certainly can’t justify the cost of required new parts, but could possibly stretch to used or reconditioned parts. Alternatively, cut my losses sell it for scrap, buy a W211 diesel or a modern hatchback lol! At the moment, it’s still running fine, except for the mpg, any suggestions?

 

[Grand Tourer]

Bump

 

[Maxbumpo]

Well it's the devil you know vs. the devil you don't, if you sell this to buy another used car. 2004 is getting pretty long in the tooth, but generally as long as you keep putting parts in them, they keep running. Generally, if you can do most of the work or at least some of the work yourself, owning an older Mercedes can be more economical than purchasing a newer "dependable" car. If you must pay someone else, any older car will probably eat you alive with repair bills, but Mercedes will be worse than some (Japanese cars) but better than others (Audi, BMW).

I'm thinking that if you buy another used Mercedes to replace this, I'd get one that is at least 3 or 4 years old, and one that had an engine and transmission that has a good reputation for dependable service (in other words, the same engine and transmission was used in many other models and had 5 or 7 years of service life in other cars, so that there are a lot of examples out there for determining the dependability).

 

[Maxbumpo]

Regarding the ABS pump, have you checked with the dealer to see if this is covered under a recall, and you can get it fixed for free?

 

[SocalSam]

Brake job was botched. Maybe guide pins were not properly lubed which is causing pad to hang. ABS light may not be pump. It could be speed sensor which is an affordable fix. Swap air suspension for coil overs and do not look back. On a side note, you need a second opinion. Mechanics will say a lot of things to get jobs.

 

[Grand Tourer]

Thanks guys, my gut feeling is this particular car is not worth saving, i’d stupidly bought a vehicle with very little service history and the mpg is poor at best. Three garages have confirmed that the SPC ABS pump very likely cause. I’m looking around for a replacement and resigned that I won’t find anything as nice to drive.

 

[Maxbumpo]

Here in the US the brake system pump for many models was covered by a recall because MB had used defective parts. Have you checked with your local MB dealer to see if the brake repair should be covered under recall?

 

[DieselBound]

Pay attention to what SocalSam wrote!

Focus on determining the brake issue as if it's not the SBC and or not an expensive fix then the suspension can be viewed as a normal consumable (in almost all cases any used vehicle will require a suspension refresh, even newer ones!)

 

[Grand Tourer]

Taking your advice guys, I drove 2 miles this evening and the back brake discs were redhot. Front discs weren’t even warm. The fact that it’s so localised and it’s the back discs and pads that were replaced when the problem started points to calipers so I’m going to get them checked out this week. Thanks for advice.

 

[Witek_M]

Taking your advice guys, I drove 2 miles this evening and the back brake discs were redhot. Front discs weren’t even warm. The fact that it’s so localised and it’s the back discs and pads that were replaced when the problem started points to calipers so I’m going to get them checked out this week. Thanks for advice.

If rear brakes are getting red hot take vehicle back to the shop that did rear brakes.

Here is market note from MBUSA dated 20/03/2008. If wrong parts were installed you will experience issue like yours.

 

[SocalSam]

Taking your advice guys, I drove 2 miles this evening and the back brake discs were redhot. Front discs weren’t even warm. The fact that it’s so localised and it’s the back discs and pads that were replaced when the problem started points to calipers so I’m going to get them checked out this week. Thanks for advice.

Hoping for positive outcome. ABC is going to be a problem in the future. Take a look at spring conversion kits:

mercedes w211 coil spring conversion kit - Google Shopping

 

[Maxbumpo]

Another possible cause is flexible brake lines are bad. They can fail internally and become check valves, so they will allow brake fluid pressure to build, but won't allow the pressure to release. If the pressure can be released by opening the bleeder valve, that's your problem.

 

[Witek_M]

Hoping for positive outcome. ABC is going to be a problem in the future. Take a look at spring conversion kits:

mercedes w211 coil spring conversion kit - Google Shopping

W211 has never had ABC.

 

[SocalSam]

Another possible cause is flexible brake lines are bad. They can fail internally and become check valves, so they will allow brake fluid pressure to build, but won't allow the pressure to release. If the pressure can be released by opening the bleeder valve, that's your problem.

Good point. Since rotors were changed, calipers were removed. If the gorillas did not properly secure calipers, they stretched rubber brake lines which is always bad.

 

[Grand Tourer]

Sorry for poor photo but this is the readout from the Star diagnostic at the garage. Are any of these serious? I’m just wondering if I fix up the brake problem weather I have other problems following straight on.

 

[DieselBound]

Did they clear everything, run/drive it and then re-scan?

 

[Witek_M]

Sorry for poor photo but this is the readout from the Star diagnostic at the garage. Are any of these serious? I’m just wondering if I fix up the brake problem weather I have other problems following straight on.

DAS produces very nice report in PDF format. Post that.

 

[Grand Tourer]

Did they clear everything, run/drive it and then re-scan?

No they didn’t. And that bit of paper is all I have.

 

[Grand Tourer]

Just to provide an update, I had the car checked by a reputable diagnostic centre and they confirmed it’s the SBC. Can’t find anywhere locally that fixes them for less than £2k so I’m looking around for alternatives but struggling to find anything as nice so I’m half contemplating actually getting the SBC fixed and just risk any future expensive repairs.

 

[DieselBound]

Look around for refurbished units. These should have the motor's brushes and such replaced as well as a new vacuum "ball." Nothing tricky or risky here. Deactivate the SBC (diagnostic tool OR just disconnect the wiring) and swap. There's work in bleeding the system afterwards but, from what I understand, it's not as scary as lots make it out to be: I'll for sure find out and I've completely disconnected ALL of my braking components (doing a restore on my car). Maybe try to find a shop that'll be OK with installing such a unit: dealer, for sure, wouldn't be OK with it.